Re: [rtcweb] Proposed Video Selection Process

Stefan Slivinski <sslivinski@lifesize.com> Thu, 21 November 2013 19:34 UTC

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From: Stefan Slivinski <sslivinski@lifesize.com>
To: "'rtcweb@ietf.org'" <rtcweb@ietf.org>
Date: Thu, 21 Nov 2013 13:31:05 -0600
Thread-Topic: [rtcweb] Proposed Video Selection Process
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Subject: Re: [rtcweb] Proposed Video Selection Process
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I'm a new comer, so just a brief intro: I have a background developing real time video codecs for embedded devices so I'm in a position to comment at a technical level within this group

For clarity purposes the proposed alternatives in Magnus' email on nov 18th; are we strictly speaking about decoders?  Historically mandatory requirements are they relate to video compatibility define just the decoders.  Obviously if there is only a single mandatory video decoder this implies a mandatory encoder, however in the case where there are 2 mandatory decoders only a single encoder is technically required.

Clarifying this is fairly important because in the case of both h264 and vp8 (and in the future vp9 and h265) the decoder complexity is fairly low and hardware acceleration is not critical but in the case of the encoders where the complexity can be 3x or worse, hardware acceleration becomes increasingly important

Stefan


----- Original Message -----
From: Adam Roach [mailto:adam@nostrum.com]
Sent: Thursday, November 21, 2013 12:58 PM
To: Magnus Westerlund <magnus.westerlund@ericsson.com>;; rtcweb@ietf.org <rtcweb@ietf.org>;
Subject: Re: [rtcweb] Proposed Video Selection Process

On 11/21/13 08:51, Magnus Westerlund wrote:
> We (WG chairs) are proposing that the working group consent to a method
> that will establish an MTI, even if the MTI chosen does not have rough
> consensus.

Although this is phrased very carefully, I think this email 
inadvertently glosses over the fact that this is a formal call for 
consensus around the proposed approach. I also think you need to be 
crystal clear -- and I'm going to borrow RFC 3929's language here -- 
"that the working group's consensus to use [this specific] method stands 
in for the working group's consensus on the technical issue."

I wanted to point this out because it would be very easy to accidentally 
read the email as an announcement for the way the codec will be 
selected, rather than a call for consensus around a proposed approach.

/a
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